There are a number of arrangements wherein a plurality of simultaneously produced electrical signals must be amplified, possibly stored and subsequently converted into useful video information which can be recorded, displayed or otherwise utilized. For example, acoustically operated imaging, testing and like systems may include an array of receiving transducer elements for converting acoustic energy impinging thereon to electrical signals. The transducer signals are supplied to a receiver having a plurality of signal processing channels for amplification, storage and gating thereof to produce the useful video signal. For operation over an extended range of input signals the amplifier means may be switched from linear to logarithmic mode. One such arrangement is shown in copending U.S. patent application Ser. No. 411,729, filed Nov. 1, 1973, the subject matter of which application is specifically incorporated herein by reference.